Development of a Novel Methodology in Predicting Transient Deicing Simulation of an Automotive Windshield

With the growing demand in passenger comfort and enhanced safety and high competitiveness in the automotive segment, automotive manufacturers are keen to launch the product flawlessly within short period of time. In that regard one of the areas related to safety of passengers which is windshield deicing, requires lot of attention and to be developed and certified well before the product launch. Computational fluid dynamics (CFD) helps in this regard to come up quickly with a feasible design solution. But with the conventional method of doing deicing requires lot of time and high cell count. Hence there is a requirement of developing a methodology which will shorten the simulation time and thus leading to shorter development time. One such development took place is in the multiphase models in CFD.

The present study focuses in introducing a novel methodology for predicting the transient deicing pattern in an automotive windshield. Simcenter STAR-CCM+ version 2021.2.1 was used for the analysis. The new method integrated two multiphase models ‘Fluid Film Melting and Solidification’ and ‘Volume of Fluid (VOF)’. The ice-water region on the windshield, taken as 3D shell, was modeled as a Fluid Film model whereas the ambient air region outside the vehicle in-contact with the ice-water layer was modeled as Volume of Fluid. A multiphase interaction was created between them. The primary application of this phase interaction model was to ensure when a fluid film can accumulate in particular areas of the geometry to form pools. In those areas, the accumulated fluid was modeled as a VOF phase rather than as a fluid film. The new methodology was correlated with the conventional methodology where the ice-water layer was modeled as 3D solid under the multiphase model of ‘Volume of Fluid’. The new methodology was found to reduce the mesh count by 45% of the original, leading to a reduction of computational time to a near 30%. The simulation results also found to be a near exact with transient ice pattern observed from wind-tunnel test result.